Cyanophenoxyacetonitriles

ABSTRACT

The preparation of cyanophenoxyacetonitriles including the uses thereof in herbicidal compositions.

United States Patent [1 1 Puttner et a1.

[451 Sept. 23, 1975 CYANOPHENOXYACETONITRILES [75] Inventors: Reinhold Puttner; Friedrich Arndt,

both of Berlin, Germany [73] Assignee: Schering Aktiengesellschaft, Berlin,

Germany 22 Filed: June 26,1973

21 Appl. No.: 373,864

[30] Foreign Application Priority Data July 13, 1972 Germany 2234817 [52] U.S. C1. 260/465 F; 71/92; 71/93; 71/94; 71/105 [51] Int. Cl. C07C 121/75 [58] Field of Search 260/465 F; 71/105 Primary ExaminerLewis Gotts Assistant ExaminerDo1ph H. Torrence Attorney, Agent, or Firm-Joseph F. Padlon [57] ABSTRACT The preparation of cyanophenoxyacetonitriles including the uses thereof in herbicidal compositions.

8 Claims, No Drawings benzonitrile as disclosed CYANOPHENOXYACETONITRILES The invention relates to new 4- in which X, and X represent halogen, have a herbicidal effect and can -be used for'combating weeds among carrots, seed sorghum, peas,.-alfalfa and peanuts without damage to the crop plants.

The halogen substituents X and X in the phenyl radical of the above formula are iodine, bromine and chlorine and are preferably identical.

Thecompounds of the invention are effective herbicidal agents against numerous .weed species as, for example, Stellariu media, Senecio vulgaris, Matricqria chammomilla, Lamium amplexicaule, Centaurea,

cyanus, Amaranthus retroflexus, Galium aparine Chrysanthemum segetum. lpomea purpurea, Polygonum lapaihiofolium. Sinapis ssp and S alanum ssp. The herbicidal compositions of the invention are applied to the weeds after emergence at rates varying from about l to kg of active agent per hectare,

depending on the weedspeciesand othervariables.

It has "further been" found that mixtures of the compounds according to the invention with other herbicides frequently show a synergistic effect. Suitable partners of herbicidal'effect may be named. For example: Carboxylic acids and their derivatives, such as 2,3,6-trichlorobenzoic acid and its salts; 2-methoxy- 3,6-dichlorobenzoic acid and its salts; 2,4-dichlorphenoxyacetic acid and its salts and esters; 2-methyl-4- chlorphenyl-alpha-propionic acid, its salts and esters, 2,2-dichloropropionic acidand its salts and esters; carbaminic acid derivatives, such as methyl-N-(3,4-

'dichlorophenyl) carbamate, phenols, such as dinitro-O- (sec.-butyl)-phenol and its salts; substituted ureas, such as l-(3'-(N-methyl-N-phenyl-carbamoyloxy)-phenyl)- 3,3-dimethyl urea; substituted triazines, such as 2- chloro-4-ethylamino-6-isopropylamino-S-triazine; diphenyl ether derivatives, such as 2,4-dichloro-4'- nitrophenyl ether; anilides, such as N-(4- chlorophenyl)-alpha, alpha dimethylvalerianic acid amide; uracils, such as 3-cyclohexyl-4,5-trimethylene uracil; nitriles, such as 2,o-dichlorobenzonitrile, as well as organic herbicides containing maleic hydra zide, 3- amino-1,2,4-triazole, N-( l l -dimethyl-2-propyl)-3 ,5- dichlorobenzamide, N,N-di-(n-propyl)-2,6-dinitro-4- 2 trifluormethyl aniline, 4-amino-3,5,6-trichloropicolinic acid and l,l-dimethyl-4,4 -bipyridinium salts.

Depending on the purpose for which used, other substances may be added, by which it must be understood that non-phytotoxic additions such as wetting agents, emulsifiers, solvents, oily additions and others give a synergistic potentiation with herbicides. The active substances according to theinvention or their mixtures are advantageously used in the form of preparations, aspowders, scatters, granulations, solutions, emulsions or suspensions, with the addition of liquid and/or solid vehicles or diluents and possibly clay, limestone, silica, and plant products, such as flours. H I

Among surface-active substances which may be named are: calcium-lignin sulfonate, polyoxyethyleneoctylphenol ether,naphthalene-sulfonic acids, phenolsulfonic acids, formaldehyde condensates, fat alcohol sulfatesand fatty acid alkali and alkaline earth salts.

The proportion of active substance or substances used in the various preparations may vary within wide limits. For example, the agents contain about 20 to 80 percent by weight of active substances, about 80 to 20 percent by weight of liquid or solid vehicles as well as possibly up to 20 percent by weight of surface-active substances. l r,

The agents may be applied in the usual manner, such as: with water as the vehicle in spray solution quantities a of 100 to 1000 liters per hectare. For total weed con- NC- (il) or their alkali salts, e.g. the potassium or sodium salt, with a compound of the general formula Hal cu CN (In) i using an organic solvent, such as acetone or dimethyl sulfoxide, in the presence of an acid acceptor, such as potassium carbonate or sodium carbonate, whereas in the general formula X and X have the above mentioned meaning and Hal isiahalogen atom.

The following examples will illustrate the production of the compounds according to the invention.

1 (2 ,6-diiodo-4-cyanophenoxy )-acetonitrile A mixture of 37.1 g (0.1 mole) 2,6-diiodo-4- cyanophenol, 9.82 g (0.13 mole) chlor acetonitrile, 13.82 g (0.1 mole) potassium carbonate and 150 ml dimethyl sulfoxide is stirred for 12 hours at 80C. The re- Compound according to invention A mixture of 5.2 g (0.028 mole) 2,6-dichloro-4- cyanophenol, 11.4 g (0.15 mole) chloroacetonitrile, 4.6 g (0.033 mole) potassium carbonate and 50 mlacetone is boiled with reflux for 16 hours while stirring.

I Then one filters and the filtrate is concentrated to dry- Physical constant 4. 2-Chloro-6-iodo-4-cyanophenoxy acetonitrile M.P.: 137-138 5. 2-Chloro-6-bromo-4-cyanophenoxy M.P.: 115-1 16 C acetonitrile 6. 2-Bromo-6-iodo-4-cyanophenoxy acetonitrile action mixture is poured into iced water and extracted 20 2. (2,6-dibromo-4-cyanophenoxy)-acetonitri1e A mixture of 13.85 g (0.05 mole) 2,6-dibromo-4- cyanophenol, 15.2 g (0.2 mole) chloracetonitrile, 7.9 g (0.056 mole) potassium carbonate and 100 ml acetone is boiled with reflux for 12 hours while stirring. Then one filters and the filtrate is evaporated under vacuum 'to dryness. The residue is recrystallized from 40 methanol.

Yield: 12.1 g 77% of the theory M.P.: 126 129 C 3. (2,6-dichloro-4-cyanophenoxy )-acetonitrile The compounds according to the invention are practically colorless and odorless crystalline substances. They are insoluble in water and gasoline and more or less soluble in acetone, tetrahydrofurane, cyclohexanone, isophorone and dimethylformamide.

The starting products for the production of the compounds according to the invention are known in the art or can be produced by methods known in the art.

The production of the preparations of the compounds according to the invention and their mixtures, ready for use, can be carried out in a well known manner, such as, by mixing or grinding. If desired, the individual components may be mixed only just before their use, as is done in the so-called tank mix process.

The following example illustrates the herbicidal effect of the compounds according to the invention.

EXAMPLE used according to the invention in a dose of 1 kg of ac tive substance per hectare. The agents were sprayed uniformly as an aqueous suspension at 500 liters per hectare. Two weeks after the treatment, the degree of damage of the plants was ascertained and rated according to the evaluation code 0 10; with 0 totallydecl stroyed and 10 not damaged".

The findings show, compared with the known herbil'. (VI) cides, the same or even a better herbicidal effect of the compounds according to the invention with greater tol- Cl erance for the crop plants.

Compounds according to invention a b 2,6-dibromo-4-cyanophenoxy acetonitrile 10 10 2,6-diiodo-4-cyanophenoxy acetonitrile l0 l0 2,6-dichloro-4-cyanophenoxy acetonitrile l0 l0 2-chloro-6-iodo-4-cyanophenoxy acetonitrile l0 l0 2-chloro-6-iodo-4-cyanophenoxy-acetonitrile l0 l0 2-bromo-6-iodo-4-cyanophenoxy acetonitrile l0 10 Comparison agent 3.5-dibromo-4-hydroxybenzonitrile l0 l0 3,5-diiodo-4-hydroxybenzonitrile l0 l0 -Continued Compounds according to invention a b c d e f Untreated control l l0 l0 l0 l0 l0 0 totally destroyed not damaged ijklmnopqr l0 l0 l0 l0 l0 l0 IO l0 10 10 a Oat b Rye c Barley d Wheat e Pea f Carrot 3 Alfalfa h Peanut i Seed sorghum j Stellaria media k Senecia vulganlr l Mamcaria chamomilla m laminrn amplexicuule n Cenraurea cyanu:

o Amaramllus relroflexu:

p Chrysanthemum :egerum q Solarium ssp.

r Sinapis up.

We claim: 1. Herbicidal compounds of the general formula in which X, and X are identical or different and represent halogen.

2. Compounds according to claim 1, where X and X represent an element selected from the groupconsisting of iodine, bromine and chlorine atom. 

1. HERBICIDAL COMPOUNDS OF THE GENERAL FORMULA
 2. Compounds according to claim 1, where X1 and X2 represent an element selected from the group consisting of iodine, bromine and chlorine atom.
 3. A compound of the formula as set forth in claim 1 which is 2, 6-diiodo-4-cyanophenoxy acetonitrile.
 4. A compound of the formula as set forth in claim 1 which is 2, 6-dibromo-4-cyanophenoxy acetonitrile.
 5. A compound of the formula as set forth in claim 1 which is 2, 6-dichloro-4-cyanophenoxy acetonitrile.
 6. A compound of the formula as set forth in claim 1 which is 2-chloro-6-iodo-4-cyanophenoxy acetonitrile.
 7. A compound of the formula as set forth in claim 1 which is 2-chloro-6-bromo-4-cyanophenoxy acetonitrile.
 8. A compound of the formula as set forth in claim 1 which is 2-bromo-6-iodo-4-cyanophenoxy acetonitrile. 